According to Aristophanes the unification between a man and a woman results in an offspring whereas the unification between a man and man results in pure satisfaction with no other strings attached (Symposium, 191c-d) Thus, according to Aristophanes it is natural for a human being to pursue pure love where love actually "is the name for our pursuit of wholeness, for our desire to be complete" (Symposium192e-193a).
Aristophanes' idea of human civilization is based on this love which is in its complete sense and this idea of love is the constant source of inspiration that makes the greatest of arts and formulates history (Symposium193c). Aristophanes also makes comments that devise the idea that the lovers with no strings attach are not able to evoke more desire as there is no structure of desire and the lovers would not be able to state anything substantial out of this union because they were unable to state what they did desire. According to Aristophanes this is the basic shortfall of human love but mentions that the desire to unite one's soul with its other half is what love truly is.
Similarly, Alcibiades states that he is basically homosexual in nature because he's crazy about beautiful boys and it is in his nature that he pursues for their love whenever and wherever it is possible (Symposium216d). Alcibiades was a soldier by profession and what he said followed a straight path with comparatively less intellectuality involved in it though he was able to express his mind and thoughts without any philosophical doctrines involved. He was clear and unrepentant in his views. He clearly stated his views on love by expressing himself as an ardent pursuer of beautiful young boys though he did mention that whatever it is Socrates remained his lifelong love and explicitly stated that only he, Alcibiades, could be the true love of Socrates.
Alcibiades explains to Socrates that as he is his only true lover, and this he can prove in a numerous way, his views to love is unscratched and pure therefore it is Alcibiades' idea of love, which corresponds with Aristophanes, which should stand true at the end. It is this reason Socrates should always support his views on love and finding a worthy lover in Alcibiades Socrates is better fit to help him reach that aim than anyone else (Symposium219c-d).
But on the other hand there was Socrates. According to Socrates "love is neither beautiful nor good- as he desires good and beautiful things, it is clear that he is, in fact, lacking these things" (Symposium 200a-201c). This was Socrates' view on love in a nutshell but he began to explain love as a whole and in totality. For this he took the help f his memories where he had a chat on the same topic with the priestess Diotima. According to Socrates Diotima was the one who taught everything about love (Symposium 201d) and most of Socrates' idea of love is based on Diotima's idea on love and her idea of 'ladder of ascent'. Everything that Socrates narrates hereon in the symposium reflects the idea of Diotima on love and Socrates is presenting proof after proof to justify her views.
According to Diotima, "love, in fact, is not a god, as he desires beautiful and good things, which the gods already have neither is he mortal- just as love's lack of beauty does not make him ugly" (Symposium 202a).